At what level one could start reading easy japanese books

Your ability to read is very dependent on you grammar level as well. In the following thread is a curated lst for starting to read Japanese!

Resources for Starting to Read Japanese Content

For conversation you can start anytime, I think, but you’ll find ourself confronted with unknown words and grammar very quickly. In that case you can say things like:

すみません、「???」は何ですか? What is “???”?

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